Recoverable ground anchor



July 25, 1 6 A. A. ONDREJKA RECOVERABLE GROUND ANCHOR 2 Sheets-Sheet 1 Filed Jan. 23, 1964 44am?" ,4. aw J A. A. ONDREJKA RECOVERABLE GROUND ANCHOR July 25, 1967 .2 Sheets-5heet 2 Filed Jan. 25, 1964 INVEN 4455197 a United States Patent 3,332,183 RECOVERABLE GROUND ANCHOR Albert A. Ondrejka, Rome, N.Y. (3200 Glenvalley Drive, Midwest City, Okla. 73110) Filed Jan. 23, 1964, Ser. No. 339,834 3 Claims. (Cl. 52-160) The invention herein described may be manufactured by or for the United States Government for governmental purposes without payment to me of any royalty thereon.

This invention relates to a recoverable anchor that can be driven into the ground with a minimum of effort and is more particularly concerned with providing a ground anchor having link arms which are expandable for increasing the resistance to pull out and retractable for facilitating withdrawal and use at another site.

Under certain conditions it is necessary and desirable to anchor various structures, masts, towers, vehicles and aircraft to prevent movement under the effects of wind, water and gravity. The problems of getting an anchor into the ground without elaborate accessory equipment are greatly aggravated by frozen ground, swampy or sandy soil. Anchors which operate satisfactorily in sandy or swampy soil usually require a larger surface area over which to distribute the pull-out load because of the poor soil bearing conditions. Invariably, anchors of this type are difiicult or impossible to attach in frozen soil. Thus, different types of anchors are usually required for various types of soil conditions. A universally operating ground anchor capable of performing its function in virtually all types of soil and having the capability of quick and easy recovery for re-use at another site would be a significant improvement over the presently known ground anchors which are generally either not recoverable or are useful only under certain specific soil conditions.

Accordingly, it is an object of the present invention to provide an easily insertable ground anchor capable of being driven into any type of soil and having a high resistance to pull out.

Another object of the invention is to provide a ground anchor that is recoverable for re-use at another site by retraction of expandable toggle members to facilitate withdrawal from the ground.

A further object of the invention is to provide a recoverable ground anchor having toggle arms which are expandable to any degree desired thereby correspondingly varying the pull-out strength.

Still another object of the invention is to provide a recoverable ground anchor having toggle arms that can be locked in either retracted or expanded position to facilitate driving, holding and recovering operations.

A still further object of the invention is to provide a recoverable ground anchor that can be driven into the ground with a minimum disturbance of earth, thereby resulting in more pull-out resistance because of the rela tively undisturbed earth in the vicinity of the anchor.

Another still further object of the invention is to provide an expandable-retractable ground anchor having multiple appendages such as chain, links or rods for expansion into a protuberance to create a bearing area at the lower end of the anchor thereby increasing the resistance to pull out.

Another object of the invention is to provide a recoverable ground anchor which is releasable so that an applied withdrawal force causes the expandable members to automatically retract thereby reducing the resistance to pull out and allowing recovery with a minimum of withdrawal force.

These and other objects, features, and advantages will become more apparent from the following description taken in conjunction with the accompanying drawings wherein:

FIGURE 1 is a view in partial section of the ground anchor ready for insertion into the earth;

FIGURE 1A is an enlarged cross-sectional view of the anchor taken along the line 1a1a of FIG. 1;

FIGURE 2 is a side view of the ground anchor of FIG. 1;

FIGURE 3 is an enlarged view of the driving head used to drive the ground anchor into the earth;

FIGURE 4 is a view in partial section of the upper portion of the ground anchor with the driving head in position for driving the anchor into the ground;

FIGURE 5 is a view in partial section of the upper portion of the ground anchor with the driving head in position for driving the outer casing downward to outwardly expand toggle members attached at the lower portion;

FIGURE 6 is a view in partial section of the ground anchor in operating position in the earth showing the toggles in expanded position;

FIGURE 7 is a view in partial section of the upper portion of ground anchor with the locking bolt removed and ready for withdrawal from the earth;

FIGURE 8 is a view of the lower portion of another embodiment of my invention wherein the toggle arms are replaced by chains; and

FIGURE 9 is a view in partial section of the lower portion of still another embodiment of the ground anchor wherein the toggle arms are replaced by a plurality of link members.

Referring now to the drawings in which like reference characters are used to refer to like parts throughout the specification, the invention includes a metal rod 13 having a pointed tip 15 at its lower end. The tip 15 is preferably fabricated of hardened steel so as to be capable of penetrating all types of soil when the rod 13 is struck on its upper end 17. The pointed tip 15 may be attached to the rod 13 by means of screw threads or a pin allowing the tip to be replaced if damaged or broken. A hollow sleeve 19 surrounds the upper portion of rod 13 and is dimensioned to allow the rod 13 to slide freely up and down therein. The hollow sleeve 19 is preferably square in cross-sectional configuration but may be circular, triangular, or have more than four Walls.

At the lower end of the sleeve 19, there is fixedly at tached a plurality .of hinge joints 21. A corresponding plurality of hinge joints 23 are fixedly attached to the upper part of the painted lower end 15. A series of hinged toggle members generally designated by the numeral 25 are attached so as to pivot on the hinge joints 21 and 23 in response to relative movement between the metal rod 13 and hollow sleeve 1'9. When the rod 13 is held stationary and the sleeve 19 is forced downward, the center portion of the toggles 25 are urged outwardly from their position against the rod 13 causing the toggle ends to pivot on the hinges 21 and 23. The toggles 25 are provided with hinges 27 which allow the toggles to hinge outwardly as the sleeve 19 moves downward. This outward movement of the toggles 25 produces a large bearing area so that the anchor will not pull out of the ground.

At various distances from the upper end of the hollow sleeve 19 there is provided a series of aligned openings 29 through which a bolt 31 may be inserted. An opening 33 in the upper end of rod 13 may be positioned in alignment with one of the openings 29. The passage of the bolt 31 through the aligned openings in the rod 13 and sleeve 19 operates to lock the members so that no relative movement will occur therebetween. With the bolt 31 in position, the toggles 25 are retained in a position governed by the relative locations of the rod 13 within the sleeve 19.

A driving head 35 shown most clearly in FIG. 3 is provided for the purpose of inserting the anchor into the ground and subsequently spreading the toggles 25. The driving head 35 includes a short end 37, a long end 39, and a shoulder portion 41 therebetween. In FIG. 4, the upper portion of the anchor is shown ready to be driven into the ground with the bolt 31 in position and the long end 39 of the driving head 35 resting against the top 17 of the metal rod 13. After the anchor has been driven the desired depth into the ground, the bolt 31 is removed and the driving head 35 is reversed so that the short end is in the sleeve 19 and the shoulder portion 41 is resting against the top of the sleeve 19, shown in FIG. 5. By driving the sleeve 19 downward while the rod 13 remains substantially stationary, the toggles 25 are forced outward thereby anchoring the structure in the soil.

In FIG. 6, the anchor is shown in the ground in operating position. A shackle 43 is pivotally fastened at the upper end of the anchor to which ropes or wires may be attached. To remove the anchor from the ground, the bolt 31 is removed and the shackle 43, attached to the sleeve 19, is pulled upward causing the toggles 25 to be retracted and allowing easy withdrawal of the anchor from the ground. The upper section of the anchor arranged for retraction and withdrawal is shown in FIG. 7.

Under certain conditions, particularly where the soil is rocky or includes a considerable amount of gravel, the embodiments of my invention shown in FIGS. 8 and 9 would operate most efiiciently. In these embodiments, the toggles 25 are replaced by the chains 45 or the links 47. The driving down of the sleeve 19 causes the chains 45 or the links 47 to form protuberances at the lower end of the anchor thereby increasing the pull-out force required to remove the anchor. Thus, if any large stones should be in the area near the anchor point 15, the chains 45 or the links 47 can conform around the stone without causing damage and the resultant pull-out force will be unusually large, Removal of anchors is accomplished in the same manner as when using toggles. Upward force on the sleeve 19 with the bolt 31 removed causes the chains 45 or the links 47 to be withdrawn back toward the rod 13 releasing the anchor and allowing easy withdrawal thereof.

In operation, the bolt 31 is positioned through the lower of openings 29 and opening 33 locking the sleeve 19 and the rod 13 together, the toggles 25 being drawn inwardly against the sides of rod 13. Driving head 35 is placed in the upper end of sleeve 19 with the long end 39 downward in contact'with the upper end of rod 13. The pointed lower end 15 of the anchor is placed at the desired angle to the ground and hammer blows are applied to the short end 37 of the driving head 35. When the desired penetration is obtained, bolt 31 is removed and the driving head 35 is reversed so that short end 37 is positioned in the sleeve 19. The shoulder portion 41 rests against the upper end of sleeve 19. Hammer blows applied to end 39 of the driving head 35 moves the sleeve downward causing the toggles 25 to pivot outwardly on hinges 21 and 23. This outward toggle action compacts the earth and results in an increase in anchor area bearing against the undisturbed earth. When the proper sleeve opening 29 is in alignment with the opening 33 in rod 13, the bolt 31 is inserted to lock the sleeve 19 and rod 13 in position with the toggles 25 expanded. A shackle 43 is attached through the top opening in sleeve 19 and any desired load can be applied to the anchor through the shackle.

To recover the anchor for reuse, the bolt 31 is removed and an upward force is applied to the shackle 43 attached to the sleeve 19. Earth bearing against the top arms of toggles 25 causes a closing action and reduces the anchor bearing area to a minimum by positioning the toggles 25 fiat against the rod 13. The anchor can then be easily withdrawn from the ground by continuing the application of upward force to the shackle 43 attached to the sleeve 19.

It should be noted that, although the hollow sleeve 19 has been shown to be square, as a practical matter it may be triangular, pentagonal, hexagonal, or have any number of sides within practical limits. Each side would have corresponding toggle, link or chain members. Also, the pointed lower end of the rod 13, although shown conical, may be pyramidal in configuration and still accomplish the desired result.

From the foregoing it will be seen that the invention has been presented with particular emphasis on certain preferred embodiments. It will be apparent to one skilled in the art that various changes, alterations, modifications and substitutions can be made in the arrangement and location of the various elements without departing from the true spirit and scope of the invention as defined in the amended claims.

Having thus set forth and disclosed the nature of my invention, what I claim is:

1. A ground anchor directly insertable into the earth by applying a downward force and recoverable by applying an upward force, said anchor comprising an elongated driving rod having a pointed lower end attached thereto, a hollow sleeve surrounding the upper portion of said rod and dimensioned to allow sliding movement of said sleeve relative to said rod, said sleeve having an upper portion extending beyond the top of said rod and having a series of aligned openings at various heights therefrom, said rod having an opening alignable with the openings in said sleeve, a plurality of protuberable elements pivotally attached between the lower end of said sleeve and the pointed lower end of said rod, locking means passing through the lower openings in said sleeve and the opening in said rod for preventing relative movement therebetween during the insertion into the earth of said anchor, the releasing of said locking means after insertion allowing said sleeve to be forced downward while said rod remains substantially stationary causing said protuberable elements to be forced outward into active position, and the placement of said locking means in the upper openings in said sleeve and the opening in said rod retaining the protuberable elements in their outward position, and means for recovering said anchor from the earth including a shackle member to which an upward force may be applied after the removal of said locking means to retract said protuberable elements inwardly while said sleeve moves upward relative to said rod thereby releasing said anchor for recovery and reuse.

2. The ground anchor defined in claim 1 wherein said hollow sleeve member has a cross-sectional configuration of straight sides and the number of said plurality of protuberable elements equal to the number of sides of said hollow sleeve, one protuberable element being provided for each side of said hollow sleeve member.

3. The ground anchor defined in claim 1 wherein the plurality of protuberable elements attached between the lower end of said sleeve and the pointed lower end of said rod includes a series of links each of which is pivotable at its contact point with the next adjacent link to permit general conformation of said protuberable elements to any irregularities in the soil composition of the area.

References Cited UNITED STATES PATENTS FRANK L. ABBOTT,

RICHARD W. COOKE, 111., Examiner.

R. S. VERMUT, Assistant Examiner.

Primary Examiner. 

1.A GROUND ANCHOR DIRECTLY INSERTABLE INTO THE EARTH BY APPLYING A DOWNWARD FORCE AND RECOVERABLE BY APPLYING AN UPWARD FORCE, SAID ANCHOR COMPRISING AN ELONGATED DRIVING ROD HAVING A POINTED LOWER END ATTACHED THERETO, A HOLLOW SLEEVE SURROUNDING THE UPPER PORTION OF SAID ROD AND DIMENSIONED TO ALLOW SLIDING MOVEMENT OF SAID SLEEVE RELATIVE TO SAID ROD, SAID SLEEVE HAVING AN UPPER PORTION EXTENDING BEYOND THE TOP OF SAID ROD AND HAVING A SERIES OF ALIGNED OPENINGS AT VARIOUS HEIGHTS THEREFROM, SAID ROD HAVING AN OPENING ALIGNABLE WITH THE OPENING IN SAID SLEEVE, A PLURALITY OF PROTUBERABLE ELEMENTS PIVOTALLY ATTACHED BETWEEN THE LOWER END OF SAID SLEEVE AND THE POINTED LOWER END OF SAID ROD, LOCKING MEANS PASSING THROUGH THE LOWER OPENINGS IN SAID SLEEVE AND THE OPENING IN SAID ROD FOR PREVENTING RELATIVE MOVEMENT THEREBETWEEN DURING THE INSERTION INTO THE EARTH OF SAID ANCHOR, THE RELEASING OF SAID LOCKING MEANS AFTER INSERTION ALLOWING SAID SLEEVE TO BE FORCED DOWNWARD WHILE SAID ROD REMAINS SUBSTANTIALLY STATIONARY CAUSING SAID PROTUBERABLE ELEMENTS TO BE FORCED OUTWARD INTO ACTIVE POSITION, AND THE PLACEMENT OF SAID LOCKING MEANS IN THE UPPER OPENINGS IN SAID SLEEVE AND THE OPENING IN SAID ROD RETAINING THE PROTUBERABLE ELEMENTS IN THEIR OUTWARD POSITION, AND MEANS FOR RECOVERING SAID ANCHOR FROM THE EARTH INCLUDING A SHACKLE MEMBER TO WHICH AN UPWARD FORCE MAY BE APPLIED AFTER THE REMOVAL OF SAID LOCKING MEANS TO RETRACT SAID PROTUBERABLE ELEMENTS INWARDLY WHILE SAID SLEEVE MOVES UPWARD RELATIVE TO SAID ROD THEREBY RELEASING SAID ANCHOR FOR RECOVERY AND REUSE. 